Left-wing demonstrators burn a German national flag on top of a house in the Mitte district of Berlin on the occasion of the 60th anniversary of the German post-war constitution May 23, 2009. Germany is marking its 60th anniversary of the post-war nation and the installation of the German Federal Republic with its pioneering constitution Grundgesetz on May 23, 1949. REUTERS/Fabrizio Bensch (GERMANY POLITICS CONFLICT ANNIVERSARY)